1. Field of the Invention
This invention relates generally to the prevention and treatment of pressure ulcers and more particularly to a system for assuring the faithful execution of a patient-repositioning regimen.
2. Antecedents of the Invention
The prevention and treatment of pressure ulcers is a significant aspect of medical care and treatment of patients at virtually all types of healthcare facilities. Indeed, pressure or pressure ulcers are a major risk for critically ill patients in hospital intensive care units, as well as the general hospital patient population, patients in long-term care facilities and patients in a home care environment.
Pressure ulcers comprise lesions resulting from reduced blood flow and/or irritation in areas over bony prominences. Unrelieved pressure at contact surfaces with a bed mattress, splint, cast or other hard object over a prolonged period constitutes the major contributing factor to reduced blood flow.
Pressure ulcers generally form at the sacrum, ischium, iliac crest, greater trochanter and at the calcaneus and external malleous. Prolonged exposure to pressure at such sites reduces the flow of blood which impedes delivery of oxygen, resulting in tissue hypoxia. Movement of the patient shifts the pressure such that the blood supply to the skin is not impaired for prolonged periods. Patients who cannot move, however, are at greater risk for developing pressure ulcers.
Among the pressure ulcer risk factors are decreased mobility, increased age, decreased cognitive abilities, nerve damage which results in diminished ability to sense pain, medications, incontinence, poor nutrition, as well as physical contact parameters, e.g. friction, shear forces, pressure levels and duration of applied pressure.
Malnourished patients may lack a protective layer of fat under the skin around bony projections and are at increased risk. In certain instances when circulation is only partially impeded, friction and shear forces due to wrinkled bedding, for example, may constitute contributing factors as well as exposure to urine or feces.
A crucial aspect of any program for prevention or treatment of pressure ulcers has been the maintenance of a patient-repositioning regimen. The use of pressure reducing mattresses without maintenance of a patient-repositioning regimen has proven insufficient.
While many long-term healthcare facilities provided caregivers with patient repositioning schedules on charts or the like, the maintenance of such schedules was not an easy task for caregivers. Different patients were on different schedules, e.g. turning cycle start time and/or cycle duration. Determinations were often required to be made by the caregiver as to the next sequential patient position. Often, a prescribed repositioning sequence was not followed due to misreading positioning information on the schedule, caregiver distractions during patient repositioning, etc.
In U.S. Pat. No. 6,014,346 to MALONE, there is disclosed a device for timing and monitoring patient sedentary inactivity which is operatively connected to a patient position sensor, a nurse call station, a remotely positioned light, etc. The MALONE device lacked portability and ease of setup. Further, the sequence of positions was not preprogrammed, such that deviations from a prescribed position sequence could occur when the healthcare provider repositioned the patient.